training-software/quizzes/models.py

import uuid

from django.conf import settings
from django.db import models


class QuestionType(models.TextChoices):
    SINGLE_CHOICE = "sc", "Single Choice"
    MULTI_CHOICE = "mc", "Multiple Choice"
    SHORT_ANSWER = "short_answer", "Short Answer"


class FeedbackMode(models.TextChoices):
    NONE = "none", "No Feedback"
    AFTER_QUESTION = "after_question", "After Each Question"
    AFTER_QUIZ = "after_quiz", "After Quiz Submission"


class AttemptStatus(models.TextChoices):
    IN_PROGRESS = "in_progress", "In Progress"
    SUBMITTED = "submitted", "Submitted"
    TIMED_OUT = "timed_out", "Timed Out"
    ABANDONED = "abandoned", "Abandoned"


class Quiz(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    # Optional FK to a Page; set for inline quizzes. Standalone quizzes may be null.
    page = models.OneToOneField(
        "courses.Page", null=True, blank=True, on_delete=models.SET_NULL, related_name="quiz"
    )
    title = models.CharField(max_length=255)
    randomize_questions = models.BooleanField(default=False)
    randomize_choices = models.BooleanField(default=False)
    pass_threshold = models.PositiveSmallIntegerField(default=70)  # percent 0-100
    max_attempts = models.PositiveSmallIntegerField(default=0)     # 0 = unlimited
    time_limit_seconds = models.PositiveIntegerField(default=0)    # 0 = no limit
    feedback_mode = models.CharField(
        max_length=20, choices=FeedbackMode.choices, default=FeedbackMode.AFTER_QUIZ
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "quizzes_quiz"

    def __str__(self):
        return self.title


class Question(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    quiz = models.ForeignKey(Quiz, on_delete=models.CASCADE, related_name="questions")
    order = models.PositiveIntegerField(default=0)
    question_type = models.CharField(max_length=20, choices=QuestionType.choices)
    text = models.TextField()
    explanation = models.TextField(blank=True)
    points = models.PositiveIntegerField(default=1)
    # Short-answer matching config
    sa_patterns = models.JSONField(default=list)  # list of regex/keyword strings
    sa_case_sensitive = models.BooleanField(default=False)
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = "quizzes_question"
        ordering = ["order"]
        constraints = [
            models.UniqueConstraint(fields=["quiz", "order"], name="unique_quiz_question_order"),
        ]

    def __str__(self):
        return f"{self.quiz.title} / Q{self.order}"


class Choice(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    question = models.ForeignKey(Question, on_delete=models.CASCADE, related_name="choices")
    order = models.PositiveIntegerField(default=0)
    text = models.CharField(max_length=1000)
    is_correct = models.BooleanField(default=False)

    class Meta:
        db_table = "quizzes_choice"
        ordering = ["order"]
        constraints = [
            models.UniqueConstraint(
                fields=["question", "order"], name="unique_question_choice_order"
            ),
        ]

    def __str__(self):
        return f"{self.question} / choice {self.order}"


class QuizAttempt(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    quiz = models.ForeignKey(Quiz, on_delete=models.CASCADE, related_name="attempts")
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="quiz_attempts"
    )
    attempt_number = models.PositiveIntegerField()
    seed = models.IntegerField()
    started_at = models.DateTimeField(auto_now_add=True)
    submitted_at = models.DateTimeField(null=True, blank=True)
    expired_at = models.DateTimeField(null=True, blank=True)
    score_percent = models.DecimalField(max_digits=5, decimal_places=2, null=True, blank=True)
    is_passed = models.BooleanField(null=True, blank=True)
    status = models.CharField(
        max_length=20, choices=AttemptStatus.choices, default=AttemptStatus.IN_PROGRESS
    )

    class Meta:
        db_table = "quizzes_attempt"
        constraints = [
            models.UniqueConstraint(
                fields=["quiz", "user", "attempt_number"],
                name="unique_quiz_user_attempt_number",
            ),
        ]

    def __str__(self):
        return f"{self.user_id} attempt#{self.attempt_number} on {self.quiz.title}"


class QuestionResponse(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    attempt = models.ForeignKey(QuizAttempt, on_delete=models.CASCADE, related_name="responses")
    question = models.ForeignKey(Question, on_delete=models.CASCADE, related_name="responses")
    selected_choice_ids = models.JSONField(default=list)  # list of UUID strings (SC/MC)
    text_response = models.TextField(blank=True)          # short_answer
    is_correct = models.BooleanField(null=True, blank=True)
    points_earned = models.PositiveIntegerField(default=0)
    answered_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        db_table = "quizzes_question_response"
        constraints = [
            models.UniqueConstraint(
                fields=["attempt", "question"], name="unique_attempt_question_response"
            ),
        ]